Warming tropics doom fauna

Global warming threatens to wipe out almost all animals unique to Australia's wet tropics by the end of the century, a rainforest expert said yesterday.

Stephen Williams, an ecologist at James Cook University, Townsville, said the annual mean temperature was expected to rise by between 1.4 degrees and 5.8 degrees by 2100.

If it rose by 5.8 degrees only about three of the 65 rainforest animals unique to the North Queensland wet tropics would remain, Dr Williams said.

A rise of 3.5 degrees would leave 30 species extinct and the rest threatened. A seven-degree rise would wipe them all out.

Dr Williams said even a rise of just one degree, likely over the next 20 to 30 years, would see off one species and leave another 20 highly endangered.

Animals potentially lost would include tree kangaroos, several species of ring-tailed possums, the chameleon gecko and the golden bowerbird.

Dr Williams said he was shocked by the preliminary findings of his long-term research into rainforest ecology.

"I expected that [climate change] might be very important . . . but I was completely blown away by how strong the potential is."

The key problem was loss of habitat, with mountainous rainforest, where most restricted species lived, likely to disappear if the temperature rose. "We'll end up still with rainforest but more like the low-land rainforest [will then be found on] the top of the mountains."

He said the only way to fight the trend was to reduce greenhouse gas emissions and protect fragile habitats.

The research, which also involved the Rainforest Co-Operative Research Centre, also found temperature change would reduce the nutritional value of foliage and increase the severity of dry seasons.

It would also mean more invasions of feral animals and weeds, a decline in seed dispersal and worse fires.